Abstract
Background Endometriosis is recognized as a complex gynecological disorder that can cause severe pain and
infertility, affecting 6–10% of all reproductive-aged women. Endometriosis is a condition in which endometrial tissue,
which normally lines the inside of the uterus, deposits in other tissues. The etiology and pathogenesis of endometrio-
sis remain ambiguous. Despite debates, it is generally agreed that endometriosis is a chronic inflammatory disease,
and patients with endometriosis appear to be in a hypercoagulable state. The coagulation system plays important
roles in hemostasis and inflammatory responses. Therefore, the purpose of this study is to use publicly available GWAS
summary statistics to examine the causal relationship between coagulation factors and the risk of endometriosis.
Methods
To investigate the causal relationship between coagulation factors and the risk of endometriosis, a two-
sample Mendelian randomization (MR) analytic framework was used. A series of quality control procedures were
followed in order to select eligible instrumental variables that were strongly associated with the exposures (vWF,
ADAMTS13, aPTT, FVIII, FXI, FVII, FX, ETP , PAI-1, protein C, and plasmin). Two independent cohorts of European ancestry
with endometriosis GWAS summary statistics were used: UK Biobank (4354 cases and 217,500 controls) and FinnGen
(8288 cases and 68,969 controls). We conducted MR analyses separately in the UK Biobank and FinnGen, followed by
a meta-analysis. The Cochran’s Q test, MR-Egger intercept test, and leave-one-out sensitivity analyses were used to
assess the heterogeneities, horizontal pleiotropy, and stabilities of SNPs in endometriosis.
Results
Our two-sample MR analysis of 11 coagulation factors in the UK Biobank suggested a reliable causal effect of
genetically predicted plasma ADAMTS13 level on decreased endometriosis risk. A negative causal effect of ADAMTS13
and a positive causal effect of vWF on endometriosis were observed in the FinnGen. In the meta-analysis, the causal
associations remained significant with a strong effect size. The MR analyses also identified potential causal effects of
ADAMTS13 and vWF on different sub-phenotypes of endometrioses.
Conclusions
Our MR analysis based on GWAS data from large-scale population studies demonstrated the causal
associations between ADAMTS13/vWF and the risk of endometriosis. These findings suggest that these coagulation
†Yan Li and Hongyan Liu contributed equally to this work.
*Correspondence:
Jianmei Wang
[email protected]
Yang Yang
[email protected]
Full list of author information is available at the end of the article
Page 2 of 13Li et al. BMC Medicine (2023) 21:195
factors are involved in the development of endometriosis and may represent potential therapeutic targets for the
management of this complex disease.
Keywords
Two-sample Mendelian randomization, Endometriosis, Coagulation, GWAS, ADAMTS13
Background
Endometriosis is defined as the deposit and growth of
endometrial tissue that normally lines the inside of the
uterus outside the uterine cavity [1]. Women who have
endometriosis are more likely to experience dysmen -
orrhea, pelvic pain, and even infertility or difficulty
conceiving. Endometriosis is a common and complex
disorder that affects up to 6–10% of all reproductive-aged
women [2]. Although many factors, including hormones,
inflammation, genetic factors, epigenetic factors, and
environmental factors, are thought to contribute to the
development of endometriosis, the etiology and patho -
genesis of endometriosis have not been completely elu -
cidated [3, 4].
Among the hypotheses that have been proposed to
explain the pathogenesis of endometriosis, retrograde
menstruation, also known as Sampson’s theory, is the
most widely accepted [4, 5]. According to the model of
retrograde menstruation, endometrial tissues are shed
through the fallopian tubes into the pelvic cavity during
menstruation, resulting in the formation of ectopic endo-
metriotic lesions on the peritoneal tissue or pelvic organs.
The ectopic debris could be cleared by the immune sys -
tem in healthy women, whereas the refluxed endometrial
fragments might evade the immune surveillance system
in endometriosis patients [6–8]. Defective immune sur -
veillance is thought to play a role in the implantation and
growth of ectopic endometrial tissue [6]. Endometrio -
sis is also considered as a chronic inflammatory disease,
owing to the presence of ectopic endometrial fragments,
which cause an increase in proinflammatory factors and
chemotactic cytokines [9–11]. Furthermore, angiogenesis
is required to replenish the supply of nutrients and oxy -
gen for the growth and survival of endometriotic lesions
[12, 13]. Coagulation cascades have been implicated in
both inflammatory responses and angiogenesis [12, 14–
16]. Several epidemiological observational studies have
found that patients with endometriosis are hypercoagu -
lable and hyperfibrinolytic [17, 18]. Plasma fibrinogen,
d-dimer, and plasminogen activator inhibitor levels are
higher in women with endometriosis when compared to
healthy controls while thrombin time and activated par -
tial thromboplastin time decrease [19]. Adenomyosis, a
condition characterized by endometrial tissue growth
within the uterine musculature, shares numerous com -
mon symptoms with endometriosis, including pelvic pain
and heavy menstrual bleeding [20]. Harmsen et al. have
reported the increased levels of von Willebrand factor in
ectopic endometrium of adenomyosis patients which are
associated with the role of angiogenesis in adenomyosis
[21]. Although several observational studies have been
conducted to explore the relationship between coagula -
tion cascades and endometriosis, the causal associations
between coagulation factors and endometriosis remain
unclear. The presence of residual confounding and poten-
tial reverse causality issues in conventional observational
studies poses significant challenges in accurately measur-
ing the causal effect of specific coagulation factor on the
risk of endometriosis. Residual confounding occurs as a
Result
of inadequate adjustment for confounding varia -
bles, as measuring a confounder may not fully character -
ize it. In addition, the association between the exposure
and outcome may occur due to reverse causality, a phe -
nomenon in which the outcome precedes and causes the
exposure, rather than the exposure causing the outcome.
As an emerging method, Mendelian randomization
(MR) is a novel statistical method that examines the
causal relationship between the exposure and outcome
by using genetic variants as instrumental variables for
the exposure of interest [22, 23]. Because genetic variants
are randomly allocated during gamete formation and
conception, MR analysis could reduce confounding bias
and reverse causality [23]. A two-sample MR analysis was
carried out in this study to investigate the causal effects
of coagulation factors on endometriosis. There were
11 coagulation factors incorporated as the exposures,
including vWF (von Willebrand factor), ADAMTS13 (A
disintegrin and metalloproteinase with thrombospondin
motifs 13), aPTT (activated partial thromboplastin time),
FVIII (factor VIII), FXI (factor XI), FVII (factor VII), FX
(factor X), ETP (endogenous thrombin potential), PAI-1
(plasminogen activator inhibitor-1), protein C, and plas -
min. We leveraged summary-level GWAS data from two
independent large-scale cohorts of European ancestry,
including the UK Biobank and FinnGen cohorts, to esti -
mate a putative causal association of a specific coagula -
tion factor with the risk of endometriosis.
Methods
Study design
Three critical assumptions must be met in the MR anal -
ysis. The first assumption is that the genetic variables
should be significantly related to the exposure, the sec -
ond assumption is that genetic variants extracted as
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Li et al. BMC Medicine (2023) 21:195
instrumental variables for the exposure are not related
to other confounding factors, and the third assump -
tion is that genetic variants influence the outcome solely
through their effects on the exposure (i.e., no horizontal
pleiotropic effect) [24]. Figure 1 depicts the overall design
of this study. We began by selecting 11 coagulation fac -
tors based on publicly available GWAS data. Based on the
GWAS summary statistics, we selected instrumental var -
iables for each coagulation factor. Then, using summary-
level GWAS data of endometriosis from two independent
cohorts, including the UK Biobank and FinnGen, we con-
ducted two-sample MR analyses separately to estimate
the causal effects of coagulation factors on endometrio -
sis. To confirm the potential causal effects of coagulation
factors, we further meta-analyzed endometriosis GWAS
summary statistics from the UK Biobank and FinnGen.
Finally, MR analyses were also performed to estimate the
causal associations of coagulation factors with the risk
of various sub-phenotypes of endometrioses, including
endometriosis of the intestine, ovary, pelvic peritoneum,
fallopian tube, uterus, rectovaginal septum, and vagina.
Endometriosis GWAS summary statistics
To obtain a reliable conclusion of the causal relation -
ships between coagulation factors and the risk of
endometriosis, we have conducted a systematic analy -
sis of endometriosis GWAS summary-level data col -
lected from two large-scale cohorts, including the UK
Biobank and FinnGen. The GWAS summary statistics
for endometriosis among individuals of European
ancestry in the UK Biobank were procured from the
Pan-UK Biobank website (https:// pan. ukbb. broad insti
tute. org/) via a phenotype description search for “endo -
metriosis” [25]. Correspondingly, the FinnGen cohort’s
endometriosis GWAS summary statistics were accessi -
ble via the R package TwoSampleMR (v 0.5.6) [26] using
the GWAS ID “finn-b-N14_ENDOMETRIOSIS” as
documented in the IEU OpenGWAS database (https://
gwas. mrcieu. ac. uk/) [27]. In the UK Biobank, the
diagnosis of endometriosis was defined by N80 in the
International Classification of Diseases, 10th Revision
(ICD-10). The GWASs for endometriosis from the UK
Biobank of European ancestry were conducted on 4354
cases and 217,500 female controls. In FinnGen, endo -
metriosis is defined by N80 in ICD-10, 617 in ICD-9,
and 6253 in ICD-8. The GWAS summary statistics for
endometriosis from FinnGen included 8288 cases and
68,969 controls. In addition, we also curated summary-
level GWAS data from the FinnGen cohort for various
sub-phenotypes of endometrioses, including endome -
triosis of the uterus (2372 cases, 68,969 controls), endo -
metriosis of the ovary (3231 cases, 68,969 controls),
endometriosis of the fallopian tube (116 cases, 68,969
controls), endometriosis of the pelvic peritoneum (2953
cases, 68,969 controls), endometriosis of the rectovagi -
nal septum and vagina (1360 cases, 68,969 controls),
and endometriosis of the intestine (177 cases, 68,969
controls).
Fig. 1 Overall design of the MR analysis framework in this study. A flow chart depicts how the MR analysis was conducted step by step in this study
Page 4 of 13Li et al. BMC Medicine (2023) 21:195
Genetic instrumental variable selection
We used instrumental variables to investigate the causal
associations between coagulation factors and endome -
triosis. We searched for GWASs of coagulation factors in
European populations to curate genetic variants associ -
ated with coagulation factors. vWF, ADAMTS13, aPTT,
FVII, FXI, FVII, FX, ETP , PAI-1, protein C, and plas -
min were chosen as the examined coagulation factors
with available genome-wide significant SNPs [28–36]
(Additional file 1: Table S1). Then, for each coagulation
factor, we went through a stringent quality control pro -
cedure to select eligible instrumental variables for each
coagulation factor. First, we selected SNPs associated
with specific coagulation factors at genome-wide signifi -
cance (P < 5e − 7) as candidate instrumental variables for
further MR analysis. Second, to ensure the instrumental
variables for each exposure phenotype are independent,
we used the linkage disequilibrium (LD)-based clumping
to remove SNPs in strong LD (r 2 threshold = 0.1, window
size = 10 Mb). The clumping step was carried out based
on the European reference panel of the 1000 Genomes
Project, which was used to estimate LD between SNPs.
For SNPs that were not present in the endometriosis
GWAS data, we used the LDlink tools to search for the
most correlated proxy SNPs using the 1000 Genomes
of European population data (r 2 > 0.8) [37]. We also dis -
carded SNPs with non-concordant alleles and palin -
dromic SNPs with ambiguous strands that could not be
corrected when harmonizing the exposure data and out -
come data. These stringently filtered SNPs were used as
the instrumental variables for subsequent MR analyses.
To determine whether there was a weak instrumental
variable bias, we calculated F-statistics to quantify the
strength of instrumental variables, where F-statistics
larger than 10 indicates a low possibility of weak instru -
mental variable bias [38, 39] (Additional file 1: Table S1).
All the instrumental variable selection and quality con -
trol steps are performed using the R package TwoSam -
pleMR (v 0.5.6) [26].
Statistical power calculation
We sought to assess the statistical power of our MR anal-
yses through the use of an online web tool specialized for
binary outcomes (https:// sb452. shiny apps. io/ power) [40].
The assessment of statistical power for MR analyses was
based on several parameters, including the total sample
size, the significance level of 0.05, the proportion of vari -
ance (R2) in the exposure explained by instrumental vari -
ables, and the ratio of cases to controls.
Mendelian randomization estimates
We combined the summary statistics (β coefficients
and standard errors) to estimate the causal associations
between 11 coagulation factors and endometriosis sepa -
rately using different MR methods. The MR analyses
were first performed separately in the UK Biobank and
FinnGen cohorts. Three MR methods based on differ -
ent assumptions were applied: inverse variance weighting
(IVW), weighted mean (WM), and MR-Egger regres -
sion. The IVW method was utilized as the main statis -
tical model. There are fixed effects and random effects
IVW methods available. We first calculated the causal
estimates using the fixed effects IVW methods by meta-
analyzing Wald ratio estimates for each instrumental var-
iable. If significant heterogeneity (P < 0.05) is observed,
the random effects IVW method is added. In addition, we
also conducted MR analyses based on the meta-analyzed
summary statistics which are combined from the UK
Biobank and FinnGen using the METAL tool [41].
Causal estimates from MR analyses can only be inter -
preted reliably if the three critical assumptions are met.
Heterogeneity in causal estimates among instrumental
variables indicates a potential violation of the assump -
tions of MR analysis [42]. The Cochran’s Q test was used
to examine the heterogeneity in causal estimates, and
we used both the causal estimates of fixed effects IVW
Method
and MR-Egger regression to detect heterogene -
ity. The heterogeneities were quantified using Cochran’s
Q statistics and a P-value smaller than 0.05 was consid -
ered significant heterogeneity. To assess the potential
pleiotropic effects of instrumental variables, the MR-
Egger regression was used. The directional horizontal
pleiotropy in the causal estimates may be indicated by the
intercept term in MR-Egger regression. Additionally, we
performed a leave-one-out analysis where we excluded
each SNP in turn and then ran MR analysis on the
remaining SNPs in order to detect potentially outlying
instrumental variables [26]. The Steiger test of direction -
ality is also conducted to assess the causal relationship
between the exposure and outcome. All MR analyses
were performed using the R package TwoSampleMR (v
0.5.6) [26].
Results
Selection of instrumental variables
We systematically curated genome-wide significant
SNPs associated with 11 coagulation factors (vWF,
ADAMTS13, aPTT, FVIII, FXI, FVII, FX, ETP , PAI-1,
protein C, and plasmin) from different GWAS results
through literature searching to examine the potential
causal effects of these coagulation factors on the risk of
endometriosis [28–36] (Additional file 1: Table S1). These
coagulation factors could be categorized into five groups,
including platelet adhesion (vWF and ADAMTS13),
intrinsic pathway (FXI, aPTT, and FVIII), extrinsic path -
way (FVII), common pathways (ETP and FX), and fibrin
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Li et al. BMC Medicine (2023) 21:195
clot dissociation (PAI-1, protein C, and plasmin). We
first kept the SNPs that were significantly associated with
each exposure phenotype in the corresponding GWAS
study (P < 5e − 7). Then, we used LD-based clumping to
obtain the LD-independent SNPs for the exposure (r 2
threshold = 0.1, window size = 10 Mb). It is critical that
the effect of an SNP on the exposure and the effect of that
on the outcome are both attributed to the same allele.
In the harmonizing process, ambiguous SNPs with non-
concordant alleles and palindromic SNPs with ambigu -
ous strands that cannot be corrected were discarded.
Therefore, the number of SNPs chosen as instrumental
variables for the exposure in subsequent two-sample
MR analyses would eventually be equal to or less than
that listed in Additional file 1: Table S1. To assess the
strength of each instrumental variable, we calculated the
F-statistics for each instrument-exposure association.
In our study, the F-statistics were much greater than 10,
indicating that those SNPs were strong instrumental vari-
ables (Additional file 1: Table S1). Moreover, we have cal-
culated the statistical power for every exposure in each
cohort. Notably, the results indicated that the statistical
power ranged from 80% to 100% for all coagulation fac -
tors, thereby affirming the robustness of our subsequent
MR analyses (Additional file 1: Table S1).
Causal effects of coagulation factors on endometriosis
Based on the GWAS summary statistics for endome -
triosis in the UK Biobank of European ancestry, which
included 4354 cases and 217,500 controls, we performed
MR analyses to estimate the causal effects of 11 coagu -
lation factors on the risk of endometriosis. The MR
estimates from different methods were shown in Addi -
tional file 1: Table S2. The findings demonstrated that the
genetically predicted plasma ADAMTS13 level is caus -
ally associated with a decreased risk of endometriosis
(IVW: OR = 0.37, 95%CI: 0.22–0.61, P = 1.25e − 4; WM:
OR = 0.41, 95%CI: 0.23–0.72, P = 2.05e − 3) (Fig. 2A,
Additional file 1: Table S2, Additional file 2: Fig. S1).
Notably, after accounting for multiple comparisons
across 11 coagulation factors, the negative causal effects
of plasma ADAMTS13 level on endometriosis remained
significant (IVW: P adjusted = 1.38e − 3). Furthermore, we
discovered a mild negative causal relationship between
genetically predicted FXI levels and endometriosis
(IVW: OR = 0.94, 95%CI: 0.89–0.98, P = 7.08e − 3; WM:
OR = 0.95, 95%CI: 0.89–1.00, P = 0.059) (Fig. 2A, Addi -
tional file 1: Table S2, Additional file 2: Fig. S1). How -
ever, other coagulation factors (vWF, aPTT, FVIII, FVII,
FX, ETP , PAI-1, protein C, and plasmin) had no signifi -
cant causal effect on endometriosis (Fig. 2A, Additional
file 1: Table S2, Additional file 2: Fig. S1). Heterogeneity
tests revealed heterogeneity in endometriosis for three
coagulation factors, vWF (IVW: Cochran’s Q = 20.35, Phet-
erogeneity = 0.041), aPTT (IVW: Cochran’s Q = 16.57, Phet-
erogeneity = 0.011), and FVIII (IVW: Cochran’s Q = 11.80,
Pheterogeneity = 0.003) (Additional file 1: Table S2). Addi -
tional MR analyses using the random effects IVW
Method
yielded causal effect estimates that were con -
sistent with those estimated using the fixed effects IVW
Method
(Additional file 1: Table S2). In the MR-Egger
intercept test, we detected no significant evidence of
horizontal pleiotropy (P pleiotropy > 0.05) (Additional file 1:
Table S2). Further leave-one-out analyses were carried
out to ascertain potential outliers in the instrumen -
tal variable estimation of ADATMS13 and FXI causal
effects on the risk of endometriosis (Additional file 1:
Table S3, Additional file 2: Fig. S2). Through the Steiger
test of directionality, the results corroborated the nega -
tive causal effects of ADAMTS13 and FXI on the risk of
endometriosis (Additional file 1: Table S2). As a result of
the MR analyses in the UK Biobank cohort, we were able
to draw a robust conclusion that the genetically predicted
plasma ADAMTS13 levels are causally associated with
a decreased risk of endometriosis, and the association
between FXI and the decreased risk of endometriosis is
likely to be causal.
As a replication analysis, we performed MR analyses
based on the GWAS summary statistics for endometriosis
in FinnGen (8288 cases and 68,969 controls). The findings
highlighted that the negative causal effects of the geneti -
cally predicted plasma ADAMTS13 level on the risk of
endometriosis remained significant with a large effect
size (IVW: OR = 0.46, 95%CI: 0.30–0.71, P = 5.31e − 4;
WM: OR = 0.53, 95%CI: 0.33–0.85, P = 0.009), which
was consistent with the findings from the UK Biobank
(Fig. 2B, Additional file 1: Table S4, Additional file 2: Fig.
S3). After multiple test correction, the causal association
estimated using fixed effects IVW method remained sig -
nificant (IVW: P adjusted = 5.8e − 3). Despite the presence
of heterogeneity in the causal estimates for ADAMTS13
on endometriosis in FinnGen (IVW: Cochran’s Q = 11.91,
Pheterogeneity = 0.003), the causal effects estimated using the
random effects IVW method remained borderline signifi-
cantly with a strong effect size (IVW: OR = 0.46, 95%CI:
0.16–0.1.34, P = 0.056) (Additional file 1: Table S4). The
Results
also showed that the genetically predicted plasma
vWF level was positively causally associated with the risk
of endometriosis (IVW: OR = 1.28, 95%CI: 1.06–1.53,
P = 0.009; WM: OR = 1.33, 95%CI: 1.08–1.62, P = 0.006),
although the effect may not remain significant after
adjusting for multiple comparisons (Fig. 2B, Additional
file 1: Table S4, Additional file 2: Fig. S3). Conversely, the
significant negative causal relationship between FXI and
endometriosis observed in the UK Biobank was not rep -
licated in FinnGen (Fig. 2B, Additional file 1: Table S3,
Page 6 of 13Li et al. BMC Medicine (2023) 21:195
Fig. 2 Causal estimates of 11 coagulation factors on endometriosis by MR analysis. A Forest plots showing causal estimates of 11 coagulation
factors on endometriosis estimated in the UK Biobank of European ancestry. B Forest plots showing causal effects of 11 coagulation factors on
endometriosis estimated in FinnGen. The odds ratio (OR) was estimated using the fixed effect IVW method. The horizontal bars represent 95%
confidence intervals (CI)
Page 7 of 13
Li et al. BMC Medicine (2023) 21:195
Additional file 2: Fig. S3). We observed no obvious hori -
zontal pleiotropy in the MR-Egger intercept test and
no potentially influential instrumental variable in the
leave-one-out analysis for ADAMTS13 and vWF (Addi -
tional file 1: Table S4 and S5, Additional file 2: Fig. S4).
The directionality of their causal effects was also con -
firmed using the Steiger test (Additional file 1: Table S4).
In conclusion, our FinnGen cohort results suggest
that ADAMTS13 levels are causally associated with a
decreased risk of endometriosis, and the positive associa -
tion observed between vWF and the risk of endometrio -
sis is likely to be causal.
With the purpose of verifying the causal effects of
coagulation factors on endometriosis, we meta-ana -
lyzed the GWAS summary statistics obtained from the
UK Biobank and FinnGen, thereby enhancing the sam -
ple size and statistical power. Subsequent MR analy -
ses were carried out using the meta-analyzed GWAS
summary statistics for endometriosis. The results sup -
ported the strong causal effect of ADAMTS13 on the
decreased risk of endometriosis (IVW: OR = 0.42,
95%CI: 0.30–0.58, P = 2.85e − 7; WM: OR = 0.44, 95%CI:
0.30–0.66, P = 5.76e − 5) (Fig. 3, Additional file 1:
Table S6, Additional file 2: Fig. S5). Notably, heteroge -
neity in causal estimates of ADAMTS13 was detected
by the heterogeneity test (IVW: Cochran’s Q = 13.23,
Pheterogeneity = 0.004), necessitating use of the random
effects IVW method to evaluate the causal association.
The result from random effects IVW analysis confirmed
the strong negative causal link between ADAMTS13
and endometriosis (Additional file 1: Table S6). The sig-
nificant MR result of vWF on the risk of endometriosis
was also observed (IVW: OR = 1.26, 95%CI: 1.09–1.46,
P = 0.002; WM: OR = 1.29, 95%CI: 1.10–1.51, P = 0.002)
(Fig. 3, Additional file 1: Table S6, Additional file 2:
Fig. S5). Moreover, the absence of potentially influen -
tial instrumental variables was ascertained by leave-
one-out analysis (Additional file 1: Table S7, Additional
file 2: Fig. S6), and the Steiger test validated the direc -
tionality of the causal effects on the risk of endome -
triosis (Additional file 1: Table S6). Summarizing the
findings from the meta-analysis, we could conclude that
the genetically predicted plasma ADAMTS13 levels
have a negative causal effect on the risk of endometrio -
sis, suggesting that ADAMTS13 serves as a protective
factor for endometriosis. Conversely, the genetically
predicted plasma vWF levels are positively associated
with the risk of endometriosis, indicating vWF function
as a risk factor for the development of endometriosis.
Fig. 3 Causal estimates of 11 coagulation factors on endometriosis in a meta-analysis. Forest plots showing causal estimates of 11 coagulation
factors on endometriosis in a meta-analysis of UK Biobank and FinnGen. The odds ratio (OR) was estimated using the fixed effect IVW method. The
horizontal bars represent 95% confidence intervals (CI)
Page 8 of 13Li et al. BMC Medicine (2023) 21:195
Causal effects of coagulation factors on different
sub‑phenotypes of endometrioses
Depending on the location and growth of ectopic endo -
metriotic lesions, endometriosis could be categorized.
The precise sub-phenotypes of endometriosis expe -
rienced by patients may have an impact on both their
symptoms as well as their chance of infertility. Endo -
metrioses of the intestine, ovary, pelvic peritoneum,
uterus, fallopian tube, and rectovaginal vaginal regions
were among the five sub-phenotypes of endometrioses
diagnosed in the FinnGen cohort. The GWAS summary
statistics of various sub-phenotypes of endometrioses
were also available in the FinnGen cohort. The number
of patients ranged from 116 in endometriosis of the fal -
lopian tube to 3231 in endometriosis of the ovary. Some
patients might have more than one sub-phenotype of
endometriosis because there was an overlap between dif -
ferent sub-phenotypes.
We employed MR analyses to further investigate the
causal effects of genetically predicted plasma levels of
ADAMTS13 and vWF on the risk of various sub-phe -
notypes of endometrioses. The findings demonstrated
that ADAMTS13 is negatively causally associated with
the risk of endometriosis of the ovary (IVW: OR = 0.48,
95%CI: 0.25–0.92, P = 0.028; WM: OR = 0.58, 95%CI:
0.2–81.20, P = 0.140), endometriosis of the pelvic peri -
toneum (IVW: OR = 0.32, 95%CI: 0.16–0.64, P = 0.001;
WM: OR = 0.40, 95%CI: 0.19–0.85, P = 0.017), and
endometriosis of the uterus (IVW: OR = 0.45, 95%CI:
0.21–0.97, P = 0.041; WM: OR = 0.44, 95%CI: 0.20–0.99,
P = 0.048) (Fig. 4, Additional file 1: Table S8). In addition,
ADAMTS13 had a negative but not statistically signifi -
cant causal effect on endometriosis of the rectovaginal
septum and vagina, and there was no evidence of a causal
effect of ADAMTS13 on endometriosis of the intestine
(Fig. 4, Additional file 1: Table S8). As heterogeneity was
detected, we conducted a random effects IVW analysis
to validate the findings (Additional file 1: Table S8). From
the random effects IVW analysis, the causal estimates of
ADAMTS13 on endometriosis of the uterus remained
borderline significant (IVW: OR = 0.45, 95%CI: 0.20-
–1.02, P = 0.051), while the causal estimates for endome -
trioses of the ovary (IVW: OR = 0.48, 95%CI: 0.13–1.79,
P = 0.274) and pelvic peritoneum (IVW: OR = 0.32,
95%CI:0.08–1.32, P = 0.116) attenuated towards non-
significance (Additional file 1: Table S8). Meanwhile, the
significant causal estimates of vWF were also observed
for endometriosis of the ovary (IVW: OR = 1.34, 95%CI:
Fig. 4 Causal estimates of vWF and ADAMTS13 on different sub-phenotypes of endometrioses. Forest plots depicting causal estimates of vWF and
ADAMTS13 on different sub-phenotypes of endometrioses in FinnGen, including endometriosis of intestine, endometriosis of ovary, endometriosis
of pelvic peritoneum, endometriosis of uterus, endometriosis of the fallopian tube, and endometriosis of the rectovaginal septum and vagina. The
odds ratio (OR) was estimated using the fixed effect IVW method. The horizontal bars represent 95% confidence intervals (CI). Significant P values
are highlighted in red
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Li et al. BMC Medicine (2023) 21:195
1.02–1.77, P = 0.035; WM: OR = 1.37, 95%CI: 1.03–1.81,
P = 0.028) and endometriosis of the pelvic peritoneum
(IVW: OR = 1.48, 95%CI: 1.11–1.97, P = 0.008; WM:
OR = 1.53, 95%CI: 1.13–2.08, P = 0.006) (Fig. 4, Addi -
tional file 1: Table S8). In summary, the evidence suggests
that ADAMTS13 may have a negative causal relationship
with endometriosis of the ovary, pelvic peritoneum, and
uterus, while vWF may have a positive causal relationship
with endometriosis of the ovary and pelvic peritoneum.
In addition, we noticed that the ratios of cases to con -
trols significantly varied across sub-phenotypes, rang -
ing from 1/594 for endometriosis of the fallopian tube to
1/21 for endometriosis of the ovary. Such disparity may
impede the statistical power of a MR study, prompting
the need to evaluate the statistical power. To establish the
validity of the results, we additionally calculated the sta -
tistical power for the MR analysis in each sub-phenotype
cohort. The statistical power was merely about 14% and
20% for sub-phenotypes of the fallopian tube and intes -
tine, respectively (Additional file 1: Table S8). Therefore,
we should draw our conclusions with cautions for these
two sub-phenotypes. In contrast, the statistical power for
the other four sub-phenotypes, including endometriosis
of the uterus, ovary, pelvic peritoneum, and rectovagi -
nal septum and vagina ranged between 80% and 1, thus
affirming the robustness of the MR results of these sub-
phenotypes (Additional file 1: Table S8).
In addition, the condition of endometriosis of the
uterus, also referred to as adenomyosis, has been cat -
egorized as a separate disease, despite its classification
as a form of endometriosis in ICD-10. Several stud -
ies have suggested that endometriosis and adenomyo -
sis share similar pathophysiology, specifically related to
somatic epithelial mutations and epigenetic abnormali -
ties. In order to determine the potential effects of incor -
porating endometriosis of the uterus in our MR study,
we employed LDSC to examine the genetic correlations
between adenomyosis and other sub-phenotypes [43, 44].
The results indicate strong genetic correlations, ranging
from 0.67 to 0.93, indicating a shared genetic architec -
ture and pathophysiological mechanisms between aden -
omyosis and endometriosis (Additional file 1: Table S9).
These findings suggest that the inclusion of adenomyosis
is unlikely to significantly impact the causal estimation of
coagulation factors on the risk of endometriosis.
Discussion
Utilizing summary statistics from two large-scale
GWASs of European ancestry including UK Biobank
and FinnGen, we investigated the causal effects of 11
coagulation factors on the risk of endometriosis, employ -
ing a unified MR framework to analyze GWAS data.
Our results indicate that genetically predicted plasma
ADAMTS13 levels were inversely associated with endo -
metriosis, while genetically predicted plasma vWF levels
demonstrated a positive causal association with endo -
metriosis, as confirmed in the meta-analysis combining
the cohorts. Furthermore, MR analyses also revealed the
causal associations in different sub-phenotypes of endo -
metrioses that are categorized by ectopic location. These
findings have significant implications for the develop -
ment of endometriosis prevention strategies and treat -
ment methods. For example, the findings underscore
the significance of monitoring the ADAMTS13 plasma
levels in individuals diagnosed with endometriosis. Fur -
thermore, the results also provide a potential therapeutic
approach that entails regulating the ADAMTS13 plasma
level, thereby enabling the management and prevention
of endometriosis progression and recurrence.
Although several factors involved in the development
of endometriosis have been uncovered, the precise etiol -
ogy and pathogenesis of endometriosis remain obscure,
and its treatment remains controversial [3, 4]. A thor -
ough understanding of endometriosis is required for
the development of effective preventative and treatment
strategies. Sampson proposed the retrograde menstrua -
tion theory, which states that menstrual blood contain -
ing endometrial cells retrograde through fallopian tubes
into the pelvic cavity instead of out of the body, leading
to the formation of ectopic endometriotic lesions [45].
Although Sampson’s theory is the most widely accepted,
several alternative hypotheses have been put forth, such
as the theories of stem cell origin and altered immunity
[46, 47]. Endometriosis is considered as a consequence
of a complex interplay of genetic, anatomical, environ -
mental, and immunologic factors [1–3]. Despite contra -
dicting accounts regarding the origin of endometriosis,
it is generally accepted that endometriosis is associated
with a local inflammatory response, and that vasculariza -
tion at the site of endometriotic invasion plays a crucial
role in the development of the lesions [48]. Notably, the
coagulation system has been acknowledged as playing
critical roles in modulating both inflammatory responses
and angiogenesis [12, 14–16]. Recently, Li et al. have
reported that the fibrinogen alpha chain could promote
the migration and invasion of endometrial cells and
promote angiogenesis in endometriosis [49–52]. Heavy
menstrual bleeding (HMB) is a prevalent clinical symp -
tom of endometriosis. Studies have raised the possibil -
ity of an imbalance in coagulation factors playing a role
in HMB in patients with endometriosis. Research has
noted that women with endometriosis exhibit a hyperco -
agulable status characterized by elevated levels of specific
coagulation factors, such as fibrinogen and vWF [17–19,
53, 54]. These elevated factors may contribute to HMB
by promoting the formation of blood clots. As such, an
Page 10 of 13Li et al. BMC Medicine (2023) 21:195
imbalanced coagulation system may represent a plausi -
ble etiologic mechanism behind HMB in endometriosis.
Despite the growing interest regarding the involvement
of coagulation factors in the pathogenesis of endometrio-
sis, the causal roles of these factors in the development of
endometriosis remain uncertain.
This is the first study to investigate the causal relation -
ships between coagulation factors and the risk of endo -
metriosis utilizing MR analyses on large-scale population
cohorts, which provided unconfounded causal estimates.
The findings highlighted that the plasma ADAMTS13
levels have a negative causal effect on endometriosis,
whereas the plasma vWF levels have a positive causal
effect on endometriosis. In other words, ADAMTS13 is
found to have a protective effect associated with endo -
metriosis, while vWF is characterized as a risk factor
for the development of the condition. The multimeric
glycoprotein vWF is stored in the Weibel-Palade bodies
and α-granules of platelets, awaiting release upon stim -
ulation. Its primary function involves the formation of
a bridge between surface receptors on platelets and the
endothelium, allowing for platelet recruitment follow -
ing an injury [55]. ADAMTS13 is a multidomain metal -
loprotease that is predominantly synthesized in the liver
by hepatic stellate cells, and its primary role is to regu -
late thrombogenesis by cleaving hyperactive ultra-large
multimers of vWFs into less active, smaller fragments
[56]. Given the vWF-cleaving function of ADAMTS13,
the biological functions of ADAMTS13 and vWF are
closely related. The thrombotic thrombocytopenic pur -
pua (TTP) that arises in people with severe ADAMTS13
deficiency has highlighted the relevance of ADAMTS13
function [57, 58]. ADAMTS13 deficiency may lead to the
accumulation of vWF multimers, which causes intravas -
cular platelet aggregation and microthrombosis, resulting
in TTP . Aside from the well-established role in hemosta-
sis, the balance between ADAMTS13 and vWF has been
linked to a variety of diseases, such as systemic inflam -
mation, pancreatitis, and multiple sclerosis [59–61]. The
biosynthesis and secretion of ADAMTS13 from vascu -
lar endothelial cells have raised the interests in the role
of ADAMTS13 in angiogenesis [62–64]. The balance
between ADAMTS13 and vWF is crucial for control -
ling angiogenesis, as demonstrated by numerous studies
[63]. In addition, Xiao et al. have recently demonstrated
the proteolytically active ADAMTS13 is expressed in the
human placental tissues and has a role in trophoblast
cell proliferation, migration, invasion, and tube forma -
tion [65]. Overall, the balance between ADAMTS13 and
vWF not only regulates hemostasis, but also exerts a role
in inflammation modulation, regulating angiogenesis,
and tissue remodeling. Our findings of this MR study
confirmed the causal roles of ADAMTS13 and vWF on
endometriosis. Although the UK Biobank and FinnGen
cohorts were utilized, there remains a need for independ-
ent validation of these causal relationships. Furthermore,
given the potential pathophysiology of endometriosis, a
more comprehensive understanding of the molecular
mechanisms and action of these coagulation factors in
endometriosis pathogenesis requires additional experi -
mental validation.
There are several strengths in this study. First, because
it is based on the fact that genetic variants are randomly
allocated during gamete formation and conception, the
Results
of MR analysis are less susceptible to confounding
bias and reverse causality [23]. Second, we employed sep-
arate samples for the exposures (coagulation factors) and
the outcome (endometriosis) data to ensure two-sam -
ple MR analyses, which avoid inflating the bias of weak
instrumental variables. Third, we incorporated two inde -
pendent large-scale cohorts for MR analyses, followed by
a meta-analysis, so that a sufficiently enough sample size
of the outcome could assure the generalizability of causal
associations. In addition, the consistent causal effect
estimates of ADAMTS13 on endometriosis among the
UK Biobank, FinnGen, and the meta-analysis alleviated
concerns on false-positive results. Fourth, we employed
multiple supplementary analyses, such as heterogeneity,
pleiotropy, and leave-one-out sensitivity analyses, to ver -
ify the viability of the assumptions regarding the instru -
mental variables.
Nonetheless, several limitations also need to be
acknowledged. First, the number of instrumental vari -
ables for each coagulation factor, as outlined in Addi -
tional file 1: Table S1 ranged from three to thirteen.
Furthermore, some instrumental variables will be dis -
carded during MR analyses when harmonizing the
exposure and outcome data. These limitations suggest
that the final MR estimates may be subject to influ -
ence from the limited number of instrumental vari -
ables. Nevertheless, the statistical power calculations
for each coagulation factor within each cohort indicate
that adequate power was achieved, with estimated sta -
tistical power ranging from 80% to 1. Therefore, despite
the potential limitations, the results presented in this
study remain sufficiently powered to draw robust con -
clusions. Second, only genome-wide significant SNPs
for different coagulation factors were available in the
exposure GWAS data, preventing us from perform -
ing bi-directional MR analyses. Third, in the context of
endometriosis, a female-specific condition, it is note -
worthy that existing GWASs examining diverse coagu -
lation factors have been conducted on a sex-combined
bias. As two-sample MR necessitates consistency in the
underlying population for both sample sets, it is impor -
tant to consider potential discrepancies with regard
Page 11 of 13
Li et al. BMC Medicine (2023) 21:195
to genetic estimates of coagulation factors in females
versus males, which may introduce bias into our MR
findings. Fourth, because this study was limited to peo -
ple of European ancestry, the findings may not be gen -
eralizable to other populations. More studies into the
causal associations between coagulation factors and
endometriosis in other populations are needed.
Conclusions
To the best of our knowledge, this is the first MR study
to examine the causal associations between coagula -
tion factors and the risk of endometriosis in the Euro -
pean population. The findings convincingly support the
causal associations between ADAMTS13/vWF and the
risk of endometriosis. This study contributes to a bet -
ter understanding of the involvement of coagulation
cascades in the development of endometriosis. These
findings may have important implications for endome -
triosis prevention and treatment strategies.
Abbreviations
CI Confidence interval
GWAS Genome-wide association study
IVW Inverse variance weighting
LD Linkage disequilibrium
MR Mendelian randomization
OR Odds ratio
RCTs Randomized controlled trials
SNP Single nucleotide polymorphism
WM Weighted mean
Supplementary Information
The online version contains supplementary material available at https:// doi.
org/ 10. 1186/ s12916- 023- 02881-z.
Additional file 1: Table S1. Selected instrumental variables for coagula-
tion factors in this study. Table S2. Summary statistics of the causal esti-
mates of coagulation factors on endometriosis in UK Biobank. Table S3.
The results of leave-one-out analyses for endometriosis in UK Biobank.
Table S4. Summary statistics of the causal estimates of coagulation fac-
tors on endometriosis in FinnGen. Table S5. The results of leave-one-out
analyses for endometriosis in FinnGen. Table S6. Summary statistics of
the causal estimates of coagulation factors on endometriosis in the meta-
analysis. Table S7. The results of leave-one-out analyses for endometriosis
in the meta-analysis. Table S8. Summary statistics of the causal estimates
of vWF and ADAMTS13 on different sub-phenotypes of endometrioses.
Table S9. Genetic correlations between endometriosis of uterus (adeno-
myosis) and other sub-phenotypes.
Additional file 2: Fig. S1. Scatter plots for MR analyses of the causal effect
of 11 coagulation factors on endometriosis in UK Biobank. Fig. S2. Plots of
leave-one-out analyses for the causal associations in UK Biobank. Fig. S3.
Scatter plots for MR analyses of the causal effect of 11 coagulation factors
on endometriosis in FinnGen. Fig. S4. Plots of leave-one-out analyses for
the causal associations in FinnGen. Fig. S5. Scatter plots for MR analyses of
the causal effect of ADAMTS13 and vWF on endometriosis in a meta-anal-
ysis. Fig. S6. Plots of leave-one-out analyses for the causal associations in
the meta-analysis.
Acknowledgements
We would like to thank the UK Biobank consortia, FinnGen consortia, GWAS
Catalog, and Neale Lab for sharing the GWAS data. We would like to thank the
anonymous reviewers for their constructive comments.
Authors’ contributions
YY, JW, and YD conceived and designed the study. YY supervised the study
and data analysis. YL and HL performed the data analysis with help from SY,
BZ, and XL. YY, JY, YL, and HL wrote the manuscript. All authors revised and
approved the final manuscript.
Funding
This study was funded by the Natural Science Foundation of China (Grant No.
32100534 and No. 32200514), Talent Excellence Program from Tianjin Medical
University (to YY).
Availability of data and materials
The GWAS summary statistics for coagulation factors are available in the
GWAS Catalog or the published article and its supplementary files. The GWAS
summary statistics for endometriosis are available on the Neale lab Pan-UK
Biobank website (https:// pan. ukbb. broad insti tute. org/) for the UKBB cohort
and the IEU GWAS database (https:// gwas. mrcieu. ac. uk/) for FinnGen [25, 27].
Declarations
Ethics approval and consent to participate
The analyses were based on publicly available data that have been approved
by relevant review boards. The UK Biobank was approved by the Research
Ethics Committee (REC reference: 21/NW/0157). The FinnGen was approved
by the Coordinating Ethics Committee of the Hospital District of Helsinki and
Uusimaa (HUS/990/2017).
Consent for publication
Not applicable.
Competing interests
The authors declare that they have no competing interests.
Author details
1 Department of Family Planning, The Second Hospital of Tianjin Medical
University, The Province and Ministry Co-Sponsored Collaborative Innova-
tion Center for Medical Epigenetics, Tianjin Key Laboratory of Inflammation
Biology, School of Basic Medical Sciences, Tianjin Medical University, Tian-
jin 300070, China. 2 State Key Laboratory of Experimental Hematology, National
Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosys-
tems, Institute of Hematology and Blood Diseases Hospital, Chinese Academy
of Medical Sciences and Peking Union Medical College, Tianjin 300020, China.
3 Department of Bioinformatics, School of Basic Medical Sciences, Tianjin Medi-
cal University, Tianjin 300070, China.
Received: 20 January 2023 Accepted: 26 April 2023
References
1. Vercellini P , Vigano P , Somigliana E, Fedele L. Endometriosis: pathogenesis
and treatment. Nat Rev Endocrinol. 2014;10(5):261–75.
2. Burney RO. The genetics and biochemistry of endometriosis. Curr Opin
Obstet Gynecol. 2013;25(4):280–6.
3. Wang Y, Nicholes K, Shih IM. The origin and pathogenesis of endometrio-
sis. Annu Rev Pathol. 2020;15:71–95.
4. Saunders PTK, Horne AW. Endometriosis: etiology, pathobiology, and
therapeutic prospects. Cell. 2021;184(11):2807–24.
5. Vercellini P , Abbiati A, Vigano P , Somigliana ED, Daguati R, Meroni F, Cro-
signani PG. Asymmetry in distribution of diaphragmatic endometriotic
lesions: evidence in favour of the menstrual reflux theory. Hum Reprod.
2007;22(9):2359–67.
Page 12 of 13Li et al. BMC Medicine (2023) 21:195
6. Christodoulakos G, Augoulea A, Lambrinoudaki I, Sioulas V, Creatsas G.
Pathogenesis of endometriosis: the role of defective ‘immunosurveillance.’
Eur J Contracept Reprod Health Care. 2007;12(3):194–202.
7. Du Y, Liu X, Guo SW. Platelets impair natural killer cell reactivity and
function in endometriosis through multiple mechanisms. Hum Reprod.
2017;32(4):794–810.
8. Yu JJ, Sun HT, Zhang ZF, Shi RX, Liu LB, Shang WQ, Wei CY, Chang KK, Shao
J, Wang MY, et al. IL15 promotes growth and invasion of endometrial
stromal cells and inhibits killing activity of NK cells in endometriosis.
Reproduction. 2016;152(2):151–60.
9. Taylor HS, Kotlyar AM, Flores VA. Endometriosis is a chronic sys-
temic disease: clinical challenges and novel innovations. Lancet.
2021;397(10276):839–52.
10. Othman Eel D, Hornung D, Salem HT, Khalifa EA, El-Metwally TH, Al-Hendy
A. Serum cytokines as biomarkers for nonsurgical prediction of endome-
triosis. Eur J Obstet Gynecol Reprod Biol. 2008;137(2):240–6.
11. Tseng JF, Ryan IP , Milam TD, Murai JT, Schriock ED, Landers DV, Taylor RN.
Interleukin-6 secretion in vitro is up-regulated in ectopic and eutopic
endometrial stromal cells from women with endometriosis. J Clin Endo-
crinol Metab. 1996;81(3):1118–22.
12. May K, Becker CM. Endometriosis and angiogenesis. Minerva Ginecol.
2008;60(3):245–54.
13. Taylor RN, Yu J, Torres PB, Schickedanz AC, Park JK, Mueller MD, Sidell N.
Mechanistic and therapeutic implications of angiogenesis in endometrio-
sis. Reprod Sci. 2009;16(2):140–6.
14. Levi M, van der Poll T. Inflammation and coagulation. Crit Care Med.
2010;38(2 Suppl):S26-34.
15. Hess R, Wujak L, Hesse C, Sewald K, Jonigk D, Warnecke G, Fieguth
HG, de Maat S, Maas C, Bonella F, et al. Coagulation factor XII regu-
lates inflammatory responses in human lungs. Thromb Haemost.
2017;117(10):1896–907.
16. Belting M, Ahamed J, Ruf W. Signaling of the tissue factor coagulation
pathway in angiogenesis and cancer. Arterioscler Thromb Vasc Biol.
2005;25(8):1545–50.
17. Vigano P , Ottolina J, Sarais V, Rebonato G, Somigliana E, Candiani
M. Coagulation status in women with endometriosis. Reprod Sci.
2018;25(4):559–65.
18. Ottolina J, Bartiromo L, Dolci C, Salmeri N, Schimberni M, Villanacci R,
Vigano P , Candiani M. Assessment of coagulation parameters in women
affected by endometriosis: validation study and systematic review of the
literature. Diagnostics (Basel). 2020;10(8):567.
19. Lin Q, Ding SJ, Zhu TH, Li TT, Huang XF, Zhang XM. Role and clinical signif-
icance of coagulation and inflammatory factors in moderate and severe
ovarian endometriosis. Zhonghua Fu Chan Ke Za Zhi. 2018;53(3):167–71.
20. Bulun SE, Yildiz S, Adli M, Chakravarti D, Parker JB, Milad M, Yang L,
Chaudhari A, Tsai S, Wei JJ et al. Endometriosis and adenomyosis: shared
pathophysiology. Fertil Steril. 2023;119(5):746–50.
21. Harmsen MJ, Wong CFC, Mijatovic V, Griffioen AW, Groenman F, Hehen-
kamp WJK, Huirne JAF. Role of angiogenesis in adenomyosis-associated
abnormal uterine bleeding and subfertility: a systematic review. Hum
Reprod Update. 2019;25(5):647–71.
22. Grover S, Del Greco MF, Stein CM, Ziegler A. Mendelian randomization.
Methods
Mol Biol. 2017;1666:581–628.
23. Verduijn M, Siegerink B, Jager KJ, Zoccali C, Dekker FW. Mendelian ran-
domization: use of genetics to enable causal inference in observational
studies. Nephrol Dial Transplant. 2010;25(5):1394–8.
24. Davies NM, Holmes MV, Davey Smith G. Reading Mendelian randomisa-
tion studies: a guide, glossary, and checklist for clinicians. BMJ. 2018;362:
k601.
25. Pan-UK Biobank. Pan-ancestry genetic analysis of the UK Biobank. 2020.
https:// pan. ukbb. broad insti tute. org.
26. Hemani G, Zheng J, Elsworth B, Wade KH, Haberland V, Baird D, Laurin
C, Burgess S, Bowden J, Langdon R, et al. The MR-Base platform sup-
ports systematic causal inference across the human phenome. Elife.
2018;7:e34408.
27. Elsworth B, Lyon M, Alexander T, Liu Y, Matthews P , Hallett J, Bates P ,
Palmer T, Haberland V, Smith GD, et al. The MRC IEU OpenGWAS data
infrastructure. 2020.
28. Sabater-Lleal M, Huffman JE, de Vries PS, Marten J, Mastrangelo MA, Song
C, Pankratz N, Ward-Caviness CK, Yanek LR, Trompet S, et al. Genome-
wide association transethnic meta-analyses identifies novel associations
regulating coagulation factor VIII and von Willebrand factor plasma levels.
Circulation. 2019;139(5):620–35.
29. Ma Q, Jacobi PM, Emmer BT, Kretz CA, Ozel AB, McGee B, Kimchi-Sarfaty
C, Ginsburg D, Li JZ, Desch KC. Genetic variants in ADAMTS13 as well as
smoking are major determinants of plasma ADAMTS13 levels. Blood Adv.
2017;1(15):1037–46.
30. de Vries PS, Sabater-Lleal M, Huffman JE, Marten J, Song C, Pankratz N,
Bartz TM, de Haan HG, Delgado GE, Eicher JD, et al. A genome-wide
association study identifies new loci for factor VII and implicates factor VII
in ischemic stroke etiology. Blood. 2019;133(9):967–77.
31. Sun BB, Maranville JC, Peters JE, Stacey D, Staley JR, Blackshaw J, Burgess
S, Jiang T, Paige E, Surendran P , et al. Genomic atlas of the human plasma
proteome. Nature. 2018;558(7708):73–9.
32. Rocanin-Arjo A, Cohen W, Carcaillon L, Frere C, Saut N, Letenneur L,
Alhenc-Gelas M, Dupuy AM, Bertrand M, Alessi MC, et al. A meta-analysis
of genome-wide association studies identifies ORM1 as a novel gene
controlling thrombin generation potential. Blood. 2014;123(5):777–85.
33. Tang W, Basu S, Kong X, Pankow JS, Aleksic N, Tan A, Cushman M, Boer-
winkle E, Folsom AR. Genome-wide association study identifies novel loci
for plasma levels of protein C: the ARIC study. Blood. 2010;116(23):5032–6.
34. Tang W, Schwienbacher C, Lopez LM, Ben-Shlomo Y, Oudot-Mellakh T,
Johnson AD, Samani NJ, Basu S, Gogele M, Davies G, et al. Genetic asso-
ciations for activated partial thromboplastin time and prothrombin time,
their gene expression profiles, and risk of coronary artery disease. Am J
Hum Genet. 2012;91(1):152–62.
35. Suhre K, Arnold M, Bhagwat AM, Cotton RJ, Engelke R, Raffler J, Sarwath
H, Thareja G, Wahl A, DeLisle RK, et al. Connecting genetic risk to disease
end points through the human blood plasma proteome. Nat Commun.
2017;8:14357.
36. Huang J, Sabater-Lleal M, Asselbergs FW, Tregouet D, Shin SY, Ding J,
Baumert J, Oudot-Mellakh T, Folkersen L, Johnson AD, et al. Genome-
wide association study for circulating levels of PAI-1 provides novel
insights into its regulation. Blood. 2012;120(24):4873–81.
37. Machiela MJ, Chanock SJ. LDlink: a web-based application for exploring
population-specific haplotype structure and linking correlated alleles of
possible functional variants. Bioinformatics. 2015;31(21):3555–7.
38. Li B, Martin EB. An approximation to the F distribution using the chi-
square distribution. Comput Stat Data Anal. 2002;40(1):21–6.
39. Georgakis MK, Gill D, Rannikmae K, Traylor M, Anderson CD, Lee JM,
Kamatani Y, Hopewell JC, Worrall BB, Bernhagen J, et al. Genetically
determined levels of circulating cytokines and risk of stroke. Circulation.
2019;139(2):256–68.
40. Burgess S. Sample size and power calculations in Mendelian randomi-
zation with a single instrumental variable and a binary outcome. Int J
Epidemiol. 2014;43(3):922–9.
41. Willer CJ, Li Y, Abecasis GR. METAL: fast and efficient meta-analysis of
genomewide association scans. Bioinformatics. 2010;26(17):2190–1.
42. Bowden J, Del Greco MF, Minelli C, Davey Smith G, Sheehan N, Thompson
J. A framework for the investigation of pleiotropy in two-sample sum-
mary data Mendelian randomization. Stat Med. 2017;36(11):1783–802.
43. Bulik-Sullivan BK, Loh PR, Finucane HK, Ripke S, Yang J, Schizophrenia
Working Group of the Psychiatric Genomics C, Patterson N, Daly MJ,
Price AL, Neale BM. LD Score regression distinguishes confounding
from polygenicity in genome-wide association studies. Nat Genet.
2015;47(3):291–5.
44. Bulik-Sullivan B, Finucane HK, Anttila V, Gusev A, Day FR, Loh PR,
ReproGen C, Psychiatric Genomics C, Genetic Consortium for Anorexia
Nervosa of the Wellcome Trust Case Control C, Dunca L, et al. An atlas
of genetic correlations across human diseases and traits. Nat Genet.
2015;47(11):1236–41.
45. Tsamantioti ES, Mahdy H. Endometriosis. In: StatPearls. edn. Treasure
Island (FL); 2022.
46. Maruyama T. A revised stem cell theory for the pathogenesis of endome-
triosis. J Pers Med. 2022;12(2):216.
47. Shigesi N, Kvaskoff M, Kirtley S, Feng Q, Fang H, Knight JC, Missmer
SA, Rahmioglu N, Zondervan KT, Becker CM. The association between
endometriosis and autoimmune diseases: a systematic review and meta-
analysis. Hum Reprod Update. 2019;25(4):486–503.
48. Koninckx PR, Fernandes R, Ussia A, Schindler L, Wattiez A, Al-Suwaidi
S, Amro B, Al-Maamari B, Hakim Z, Tahlak M. Pathogenesis based
Page 13 of 13
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diagnosis and treatment of endometriosis. Front Endocrinol (Lausanne).
2021;12:745548.
49. Li H, Cai E, Cheng H, Ye X, Ma R, Zhu H, Chang X. FGA controls VEGFA
secretion to promote angiogenesis by activating the VEGFR2-FAK signal-
ling pathway. Front Endocrinol (Lausanne). 2022;13:791860.
50. Zhao Y, Liu YN, Li Y, Tian L, Ye X, Cui H, Chang XH. Identification of bio-
markers for endometriosis using clinical proteomics. Chin Med J (Engl).
2015;128(4):520–7.
51. Chen Y, Li H, Cheng HY, Rui-Qiong M, Ye X, Cui H, Hong-Lan Z, Chang XH.
Fibrinogen alpha chain is up-regulated and affects the pathogenesis of
endometriosis. Reprod Biomed Online. 2019;39(6):893–904.
52. Li H, Ma RQ, Cheng HY, Ye X, Zhu HL, Chang XH. Fibrinogen alpha chain
promotes the migration and invasion of human endometrial stromal cells
in endometriosis through focal adhesion kinase/protein kinase B/matrix
metallopeptidase 2 pathway†. Biol Reprod. 2020;103(4):779–90.
53. Rizzello F, Ralli E, Romanelli C, Coccia ME. Severe recurrent endometrio-
mas in a young woman with congenital von Willebrand disease. Gynecol
Endocrinol. 2019;35(12):1040–2.
54. Yang B, Gu N, Shi S, Zhang C, Chen L, Ouyang J, Lin Y, Sun F, Xu H. Immu-
noreactivity of plasminogen activator inhibitor 1 and its correlation with
enomyosis. Reprod Sci. 2021;28(8):2378–86.
55. Bryckaert M, Rosa JP , Denis CV, Lenting PJ. Of von Willebrand factor and
platelets. Cell Mol Life Sci. 2015;72(2):307–26.
56. Crawley JT, de Groot R, Xiang Y, Luken BM, Lane DA. Unraveling the scis-
sile bond: how ADAMTS13 recognizes and cleaves von Willebrand factor.
Blood. 2011;118(12):3212–21.
57. Warwicker P , Goodship JA, Goodship TH. von Willebrand factor-cleaving
protease in thrombotic thrombocytopenic purpura and the hemolytic-
uremic syndrome. N Engl J Med. 1999;340(17):1368–9.
58. Tsai HM, Lian EC. Antibodies to von Willebrand factor-cleaving pro-
tease in acute thrombotic thrombocytopenic purpura. N Engl J Med.
1998;339(22):1585–94.
59. Reiter RA, Varadi K, Turecek PL, Jilma B, Knobl P . Changes in ADAMTS13
(von-Willebrand-factor-cleaving protease) activity after induced release
of von Willebrand factor during acute systemic inflammation. Thromb
Haemost. 2005;93(3):554–8.
60. Morioka C, Uemura M, Matsuyama T, Matsumoto M, Kato S, Ishikawa M,
Ishizashi H, Fujimoto M, Sawai M, Yoshida M, et al. Plasma ADAMTS13
activity parallels the APACHE II score, reflecting an early prognostic indi-
cator for patients with severe acute pancreatitis. Scand J Gastroenterol.
2008;43(11):1387–96.
61. Lu K, Liu L, Xu X, Zhao F, Deng J, Tang X, Wang X, Zhao BQ, Zhang X,
Zhao Y. ADAMTS13 ameliorates inflammatory responses in experimental
autoimmune encephalomyelitis. J Neuroinflammation. 2020;17(1):67.
62. Randi AM. Angiogenesis and the ADAMTS13-VWF balance. Blood.
2017;130(1):1–2.
63. Xu H, Cao Y, Yang X, Cai P , Kang L, Zhu X, Luo H, Lu L, Wei L, Bai X, et al.
ADAMTS13 controls vascular remodeling by modifying VWF reactivity
during stroke recovery. Blood. 2017;130(1):11–22.
64. Shang D, Zheng XW, Niiya M, Zheng XL. Apical sorting of ADAMTS13 in
vascular endothelial cells and Madin-Darby canine kidney cells depends
on the CUB domains and their association with lipid rafts. Blood.
2006;108(7):2207–15.
65. Xiao J, Feng Y, Li X, Li W, Fan L, Liu J, Zeng X, Chen K, Chen X, Zhou X,
et al. Expression of ADAMTS13 in normal and abnormal placentae and
its potential role in angiogenesis and placenta development. Arterioscler
Thromb Vasc Biol. 2017;37(9):1748–56.
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